Well I was give some coilovers that were apart,all the race car one I worked on would extend enough to change springs,the ones I got were no way going on so I called the tech line,I believe carrera and he said it is normal to have to compress them to get them on which I thought was stupid so i had a plate with the right sized hole to fit the upper collar,I put them in the press upside down and compressed the spring and inserted the upper collar. You supposed to get the shock in the middle of travel so when you install them on the car if it doesn't compress them enough I suppose you have the wrong rate spring.Do any of these companies have springs for you to try so you can swap them out for the correct ones?Most of the spring were calculated off of weight,but some of that weight is sprung and some is sprung weight,so most of the time the spring is too stiff.